Grinding Reverse- Rough Shift
Thread Starter
Instructor
Joined: Nov 2011
Posts: 105
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From: Nashville TN
Grinding Reverse- Rough Shift
I have an 85 with 50k miles with a 4+3 DN that has a little trick to get it into reverse. As long as you put it into any forward gear then shift directly into reverse, it goes in fine. If it sits in neutral for any length of time and try to shift into reverse, it grinds like hell. I have had the car for 3 years/20K miles and it's always been this way. I was so excited when I bought the car that when the PO told me about this, I could have cared less. It seemed OK to me and after all, I was buying my first Vette! Everything else was perfect.
I now have a 90 ZR1 and may have to sell the ol' 85 and while this little trick has never really bothered me, the new owner may have a concern. Syncromesh issues??? It also seems to shift a little rough over all. I had the trans and OD serviced about 10K miles ago and have not really noticed any change after. I hear that the Synthetic can sometimes smooth things out a bit. To be honest, it never really bothered me until I experienced a very smooth ZF6.
I now have a 90 ZR1 and may have to sell the ol' 85 and while this little trick has never really bothered me, the new owner may have a concern. Syncromesh issues??? It also seems to shift a little rough over all. I had the trans and OD serviced about 10K miles ago and have not really noticed any change after. I hear that the Synthetic can sometimes smooth things out a bit. To be honest, it never really bothered me until I experienced a very smooth ZF6.
Team Owner
Joined: Dec 1999
Posts: 34,873
Likes: 487
From: Lacey WA RVN 68-69
NCM Sinkhole Donor
My 87 with the 4+3 did that same thing when I bought it. It was a worn-out clutch disc. Replaced the clutch, pressure plate, and throwout bearing and all was fine.
Don't use synthetic gear lube in either the 4-speed part or in the OD.
Don't use synthetic gear lube in either the 4-speed part or in the OD.
Safety Car
Joined: Jan 2004
Posts: 3,556
Likes: 13
Clutch is not disengaging fully
Also check out the hydraulics;
slave cyl may not have full travel due to wear or leaks ( not uncommon ) in master or slave cyls
Be worth flushing and bleeding the system to see if it improves things
Safety Car
Joined: Sep 2001
Posts: 4,150
Likes: 551
From: Glenbeulah Wi
Safety Car
Joined: Nov 2008
Posts: 4,328
Likes: 15
From: Jacksonville FL
Your symptoms indicate both disc wear and/or hydraulics. Does it get easier to shift if you pump the clutch? If it does you can replace both master and slave for about $75 and $5 in brake fluid.
Good luck!
Good luck!
